OMI/Aura DOAS Total Column Ozone 1-Orbit L2 Swath 13x24 km V004 (OMDOAO3) at GES DISC

The Level-2 Aura Ozone Monitoring Instrument (OMI) Ozone (O3) DOAS Total Column Product (OMDOAO3) version 4 is now available from NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) for public access. The shortname for this Level-2 Ozone Product is OMDOAO3_V004. The data was re-processed in December 2022 using collection 4 Level 1b data and the OMDOAO3 processor version 4.1.0. Since then, this version of the product is also being produced in the forward stream. This version of the product was publicly released in March 2026.

OMI provides two total column ozone products based on two different algorithms. This level-2 global total column ozone product at the pixel resolution (13x24 km at nadir), is based on the Differential Absorption Spectroscopy (DOAS) fitting technique that essentially uses the OMI UV radiance values between 331.1 and 336.1 nm. In addition to the total ozone column this product also contains auxiliary , derived and ancillary input parameters e.g. ozone slant column density, ozone ghost column density, air mass factor, scene reflectivity, radiance over the DOAS fit window, root mean square of DAOS fit, cloud fraction, cloud radiance, cloud pressure, terrain height, geolocation, viewing angles and quality flags. The lead scientist for this product is Dr. J. Pepijn Veefkind.

The OMDOAO3 files are stored in NetCDF 4 format. Each file contains data from the day lit portion of an orbit (~53 minutes). There are approximately 14 orbits per day. The maximum file size for the OMDOAO3 data product is about 10 Mbytes.